/* ==========================================================================
   Tennis Evolution — public site
   Dark court ink (#0A0F0C) + warm paper (#F1EDE2), tennis-lime (#C9F24B),
   clay (#E86A3A). System fonts only, no build step, no external requests.
   ========================================================================== */

/* ---------- tokens ---------- */
:root {
  --ink: #0a0f0c;
  --ink-2: #0e1512;
  --ink-3: #121b17;
  --paper: #f1ede2;
  --paper-2: #e8e2d3;
  --text: #f4f2ea;
  --muted: #97a69e;
  --dim: #6c7b74;
  --lime: #c9f24b;
  --lime-deep: #a8cf35;
  --clay: #e86a3a;
  --line: rgba(244, 242, 234, 0.1);
  --line-strong: rgba(244, 242, 234, 0.2);
  --line-ink: rgba(19, 26, 21, 0.14);
  --line-ink-strong: rgba(19, 26, 21, 0.26);
  --ink-text: #131a15;
  --ink-muted: #5b665e;
  --olive: #4d6411;

  --sans: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI", Inter, system-ui,
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, monospace;
  --gut: clamp(20px, 5vw, 56px);
  --sec-y: clamp(64px, 8.5vw, 116px);
  --radius: 20px;
  --radius-sm: 12px;
  color-scheme: dark;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
  overflow-x: hidden;
}

body {
  margin: 0;
  background: var(--ink);
  color: var(--text);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.62;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(900px 520px at 78% -8%, rgba(201, 242, 75, 0.07), transparent 64%),
    radial-gradient(760px 460px at 2% 34%, rgba(232, 106, 58, 0.045), transparent 66%),
    linear-gradient(180deg, #0a0f0c 0%, #090d0b 100%);
}

img,
video {
  max-width: 100%;
}

a {
  color: inherit;
  text-underline-offset: 3px;
}

::selection {
  background: var(--lime);
  color: var(--ink);
}

:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: 3px;
  border-radius: 3px;
}

/* ---------- small utilities ---------- */
.wrap {
  width: min(1240px, calc(100% - 2 * var(--gut)));
  margin-inline: auto;
}

.mono {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0;
}

.num {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
}

.lime {
  color: var(--lime);
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip {
  position: absolute;
  left: 16px;
  top: -60px;
  z-index: 60;
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--lime);
  color: var(--ink);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: top 0.18s ease;
}

.skip:focus {
  top: 12px;
}

/* ---------- header ---------- */
.site-head {
  position: sticky;
  top: 0;
  z-index: 40;
  border-bottom: 1px solid var(--line);
  background: rgba(10, 15, 12, 0.82);
  -webkit-backdrop-filter: blur(16px);
  backdrop-filter: blur(16px);
}

.site-head.is-stuck {
  background: rgba(10, 15, 12, 0.93);
  border-bottom-color: var(--line-strong);
}

.head-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  height: 68px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  font-size: 15px;
  font-weight: 650;
  letter-spacing: -0.015em;
  text-decoration: none;
  white-space: nowrap;
}

.brand-ball {
  position: relative;
  width: 22px;
  height: 22px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--lime);
  box-shadow: 0 0 22px rgba(201, 242, 75, 0.34);
}

.brand-ball::before,
.brand-ball::after {
  content: "";
  position: absolute;
  inset: 2px 4px;
  border-radius: 50%;
  border: 1.5px solid rgba(10, 15, 12, 0.5);
  border-color: transparent rgba(10, 15, 12, 0.45);
}

.brand-ball::after {
  transform: rotate(90deg);
}

.brand-sub {
  color: var(--dim);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.02em;
}

.nav {
  display: flex;
  align-items: center;
  gap: 26px;
  margin-left: auto;
  font-size: 14px;
}

.nav a {
  color: var(--muted);
  text-decoration: none;
  transition: color 0.16s ease;
}

.nav a:hover {
  color: var(--text);
}

.head-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.head-btn {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  height: 36px;
  padding: 0 15px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  font-size: 13px;
  color: var(--text);
  text-decoration: none;
  transition: border-color 0.16s ease, color 0.16s ease, background 0.16s ease;
}

.head-btn:hover {
  border-color: var(--lime);
  color: var(--lime);
}

.head-btn.lang {
  font-weight: 600;
}

.head-btn.lang span {
  color: var(--dim);
  font-weight: 400;
}

/* ---------- hero ---------- */
.hero {
  padding: clamp(40px, 6vw, 78px) 0 0;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
}

.eyebrow::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--lime);
  box-shadow: 0 0 12px rgba(201, 242, 75, 0.8);
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.62fr) minmax(280px, 1fr);
  gap: clamp(34px, 5.5vw, 84px);
  align-items: end;
  margin-top: clamp(22px, 3vw, 34px);
}

h1 {
  margin: 0;
  font-size: clamp(3rem, 5.4vw, 5.4rem);
  line-height: 1;
  font-weight: 700;
  letter-spacing: -0.04em;
  text-wrap: balance;
}

h1 .hl {
  color: var(--lime);
}

h1 em {
  font-style: normal;
}

.lede {
  margin: clamp(22px, 2.6vw, 30px) 0 0;
  max-width: 56ch;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.7;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(26px, 3.2vw, 38px);
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 15px 26px;
  border: 1px solid transparent;
  border-radius: 999px;
  font: inherit;
  font-size: 15px;
  font-weight: 620;
  letter-spacing: -0.01em;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.18s ease, background 0.18s ease, border-color 0.18s ease,
    color 0.18s ease;
}

.btn .arrow {
  transition: transform 0.18s ease;
}

.btn-primary {
  background: var(--lime);
  color: var(--ink);
}

.btn-primary:hover {
  background: #d8fa72;
  transform: translateY(-1px);
}

.btn-primary:hover .arrow {
  transform: translateY(2px);
}

.btn-ghost {
  border-color: var(--line-strong);
  color: var(--text);
}

.btn-ghost:hover {
  border-color: var(--lime);
  color: var(--lime);
}

/* hero facts column */
.hero-facts {
  border-top: 1px solid var(--line-strong);
  padding-top: 18px;
}

.facts-label {
  margin: 0 0 4px;
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--dim);
  text-transform: uppercase;
}

.facts {
  margin: 0;
}

.facts > div {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 13px 0;
  border-bottom: 1px solid var(--line);
}

.facts > div:last-child {
  border-bottom: 0;
}

.facts dt {
  color: var(--muted);
  font-size: 13px;
}

.facts dd {
  margin: 0;
  font-size: 25px;
  font-weight: 500;
  color: var(--text);
  white-space: nowrap;
}

.facts dd .arrow {
  color: var(--dim);
  font-size: 17px;
  padding: 0 4px;
}

.facts dd .unit {
  font-family: var(--sans);
  font-size: 13px;
  letter-spacing: 0;
  color: var(--muted);
  margin-left: 5px;
}

.facts dd .pass {
  display: inline-block;
  margin-left: 8px;
  padding: 2px 8px;
  border-radius: 999px;
  background: rgba(201, 242, 75, 0.14);
  color: var(--lime);
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.1em;
  vertical-align: 2px;
}

.facts-note {
  margin: 16px 0 0;
  color: var(--dim);
  font-size: 12.5px;
  line-height: 1.6;
}

/* source → reel diagram */
.record {
  margin-top: clamp(44px, 6vw, 76px);
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.record-k {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  margin: 0;
  font-size: 10.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--dim);
}

.record-k > span:first-child {
  flex: 0 0 auto;
  white-space: nowrap;
}

.record-k b {
  color: var(--muted);
  font-weight: 500;
}

.record-k-end {
  margin-top: 14px;
}

.track {
  position: relative;
  margin-top: 12px;
}

.track-src {
  height: 34px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(244, 242, 234, 0.035);
  margin-bottom: 34px;
}

.track-src .rs {
  position: absolute;
  top: 6px;
  bottom: 6px;
  min-width: 4px;
  border-radius: 3px;
  background: var(--lime);
}

.track-src .rs1 {
  left: 4.74%;
  width: 2.03%;
}

.track-src .rs2 {
  left: 31.24%;
  width: 1.84%;
}

.track-src .rs3 {
  left: 57.35%;
  width: 1.36%;
}

.track-src .rs4 {
  left: 72.59%;
  width: 1.43%;
}

.track-src .rs5 {
  left: 81.74%;
  width: 1.39%;
}

.track-src .rs::after {
  content: attr(data-t);
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.04em;
  color: var(--dim);
  white-space: nowrap;
}

.track-src .rs1::after {
  left: 0;
  transform: none;
}

.track-src .rs5::after {
  left: auto;
  right: 0;
  transform: none;
}

/* one continuous line between the two bars */
.record-join {
  display: flex;
  align-items: center;
  gap: 14px;
  margin: 0 0 10px;
  font-size: 10.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--dim);
}

.record-join::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--line);
}

.track-reel {
  display: flex;
  gap: 2px;
  height: 46px;
  margin-top: 12px;
}

.track-reel > span {
  flex: 0 0 auto;
  min-width: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--lime);
  color: var(--ink);
  border-radius: 4px;
  font-family: var(--mono);
  font-size: 14px;
  font-weight: 600;
}

.track-reel > span:nth-child(1) {
  flex-grow: 25.2;
}

.track-reel > span:nth-child(2) {
  flex-grow: 22.9;
}

.track-reel > span:nth-child(3) {
  flex-grow: 16.9;
}

.track-reel > span:nth-child(4) {
  flex-grow: 17.8;
}

.track-reel > span:nth-child(5) {
  flex-grow: 17.3;
}

.track-reel > span:nth-child(4),
.track-reel > span:nth-child(5) {
  background: rgba(201, 242, 75, 0.55);
}

/* ---------- section shell ---------- */
.section {
  padding: var(--sec-y) 0 0;
}

.section:last-child {
  padding-bottom: var(--sec-y);
}

.sec-head {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
  gap: clamp(20px, 4vw, 64px);
  align-items: end;
  margin-bottom: clamp(28px, 4vw, 46px);
}

.sec-index {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 14px;
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--dim);
}

.sec-index::before {
  content: "";
  width: 26px;
  height: 1px;
  background: var(--line-strong);
}

h2 {
  margin: 0;
  font-size: clamp(2rem, 3.5vw, 3.4rem);
  line-height: 1.04;
  font-weight: 680;
  letter-spacing: -0.035em;
  text-wrap: balance;
}

.sec-lede {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.7;
  max-width: 46ch;
}

/* ---------- media frames (placeholders read as court graphics when an
   asset has not landed yet) ---------- */
[data-media] {
  position: relative;
  background:
    radial-gradient(120% 120% at 50% 0%, rgba(201, 242, 75, 0.045), transparent 62%),
    var(--ink-3);
}

[data-media].is-missing {
  background:
    repeating-linear-gradient(90deg, transparent 0 79px, rgba(201, 242, 75, 0.055) 79px 80px),
    repeating-linear-gradient(0deg, transparent 0 79px, rgba(201, 242, 75, 0.055) 79px 80px),
    radial-gradient(120% 120% at 50% 0%, rgba(201, 242, 75, 0.05), transparent 62%),
    var(--ink-3);
}

[data-media].is-missing img {
  visibility: hidden;
}

.media-frame {
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  overflow: hidden;
}

.media-frame video,
.media-frame img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  background: transparent;
}

.media-16x9 {
  aspect-ratio: 16 / 9;
}

/* ---------- before / after ---------- */
.compare-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 16px;
}

.seg {
  display: inline-flex;
  gap: 2px;
  padding: 4px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  background: rgba(244, 242, 234, 0.03);
}

.seg-btn {
  border: 0;
  border-radius: 999px;
  padding: 9px 18px;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 13.5px;
  cursor: pointer;
  transition: background 0.16s ease, color 0.16s ease;
}

.seg-btn:hover {
  color: var(--text);
}

.seg-btn[aria-pressed="true"] {
  background: var(--lime);
  color: var(--ink);
  font-weight: 620;
}

.compare-file {
  margin: 0;
  font-size: 11.5px;
  color: var(--dim);
  letter-spacing: 0.02em;
}

.compare-file .dot {
  display: inline-block;
  width: 6px;
  height: 6px;
  margin-right: 8px;
  border-radius: 50%;
  background: var(--clay);
  vertical-align: 1px;
}

.compare-note {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 14.5px;
  line-height: 1.65;
}

.compare-note span {
  flex: 0 0 auto;
  color: var(--dim);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  padding-top: 2px;
}

/* ---------- demo ---------- */
.player {
  border-radius: 24px;
}

.player video {
  aspect-ratio: 16 / 9;
}

.player-cover {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  gap: 0;
  pointer-events: none;
  background: linear-gradient(to top, rgba(6, 10, 8, 0.55), rgba(6, 10, 8, 0.1));
  transition: opacity 0.24s ease, visibility 0.24s;
}

.player.is-playing .player-cover,
.player.has-played .player-cover {
  opacity: 0;
  visibility: hidden;
}

.player-cover-btn {
  pointer-events: auto;
  display: inline-flex;
  align-items: center;
  gap: 14px;
  padding: 12px 22px 12px 12px;
  border: 1px solid rgba(244, 242, 234, 0.32);
  border-radius: 999px;
  background: rgba(10, 15, 12, 0.58);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  color: var(--text);
  font: inherit;
  font-size: 14.5px;
  font-weight: 600;
  cursor: pointer;
  transition: border-color 0.18s ease, background 0.18s ease, transform 0.18s ease;
}

.player-cover-btn:hover {
  border-color: var(--lime);
  background: rgba(10, 15, 12, 0.76);
  transform: translateY(-1px);
}

.player-ring {
  position: relative;
  width: 46px;
  height: 46px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--lime);
  color: var(--ink);
  box-shadow: 0 0 0 6px rgba(201, 242, 75, 0.14);
}

.player-ring::after {
  content: "";
  position: absolute;
  left: 19px;
  top: 15px;
  border-style: solid;
  border-width: 8px 0 8px 13px;
  border-color: transparent transparent transparent var(--ink);
}

.player-meta {
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--dim);
}

.player-meta strong {
  color: var(--muted);
  font-weight: 500;
}

.demo-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  margin: 14px 0 0;
  color: var(--dim);
  font-size: 11.5px;
  letter-spacing: 0.04em;
}

.demo-sample {
  margin: 12px 0 0;
  color: var(--dim);
  font-size: 11.5px;
  line-height: 1.7;
  letter-spacing: 0.02em;
}

.demo-note {
  margin: 30px 0 0;
  max-width: 66ch;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.7;
}

.clips {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(16px, 2.2vw, 26px);
  margin-top: clamp(28px, 4vw, 44px);
}

.clip {
  min-width: 0;
}

.clip .media-frame {
  border-radius: 16px;
}

.clip video {
  aspect-ratio: 16 / 9;
}

.clip-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 14px;
  margin-top: 14px;
  padding-top: 13px;
  border-top: 1px solid var(--line);
}

.clip-k {
  flex: 0 0 100%;
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin: 0;
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--dim);
}

.clip-dur {
  letter-spacing: 0.04em;
  color: var(--muted);
}

.clip-hits {
  flex: 0 0 100%;
  margin: 0;
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: 27px;
  font-weight: 600;
  letter-spacing: -0.03em;
  color: var(--lime);
}

.clip-hits span {
  font-family: var(--sans);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0;
  color: var(--muted);
  margin-left: 6px;
}

.clip-src {
  flex: 0 0 100%;
  margin: 0;
  color: var(--dim);
  font-size: 12px;
  letter-spacing: 0.02em;
}

/* ---------- paper spread ---------- */
.paper {
  margin-top: var(--sec-y);
  background: var(--paper);
  color: var(--ink-text);
}

.paper .sec-index {
  color: var(--olive);
}

.paper .sec-index::before {
  background: var(--line-ink-strong);
}

.paper .sec-lede {
  color: var(--ink-muted);
}

.paper .section {
  padding-top: var(--sec-y);
}

.paper .section + .section {
  padding-top: clamp(48px, 6vw, 84px);
}

.paper .section:last-child {
  padding-bottom: var(--sec-y);
}

.paper h2,
.paper h3 {
  color: var(--ink-text);
}

.paper :focus-visible {
  outline-color: var(--olive);
}

.paper ::selection {
  background: var(--ink-text);
  color: var(--paper);
}

/* steps */
.steps {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line-ink-strong);
  counter-reset: step;
}

.step {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr) 150px;
  gap: 10px clamp(18px, 3vw, 42px);
  align-items: start;
  padding: clamp(24px, 3vw, 34px) 0;
  border-bottom: 1px solid var(--line-ink);
}

.step-n {
  padding-top: 5px;
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--olive);
}

.step-body h3 {
  margin: 0 0 9px;
  font-size: clamp(19px, 1.9vw, 25px);
  font-weight: 660;
  letter-spacing: -0.022em;
  line-height: 1.2;
}

.step-body p {
  margin: 0;
  max-width: 66ch;
  color: var(--ink-muted);
  font-size: 15.5px;
  line-height: 1.68;
}

.step-tag {
  padding-top: 7px;
  text-align: right;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-muted);
}

/* outputs */
.out-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
  gap: clamp(30px, 5vw, 72px);
  align-items: start;
}

.files {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line-ink-strong);
}

.files li {
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
  gap: 8px 22px;
  align-items: baseline;
  padding: 15px 0;
  border-bottom: 1px solid var(--line-ink);
}

.files code {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--ink-text);
  background: rgba(19, 26, 21, 0.06);
  border-radius: 5px;
  padding: 3px 7px;
  justify-self: start;
  white-space: nowrap;
}

.files span {
  color: var(--ink-muted);
  font-size: 14px;
  line-height: 1.5;
}

.manifest-quote {
  margin: clamp(24px, 3vw, 34px) 0 0;
  padding-left: 18px;
  border-left: 2px solid var(--lime-deep);
  color: var(--ink-text);
  font-size: 16px;
  line-height: 1.6;
  max-width: 52ch;
}

.manifest-quote em {
  font-style: normal;
  color: var(--ink-muted);
  display: block;
  margin-top: 6px;
  font-size: 13.5px;
}

/* label anatomy — wide 16:9 product shot, not a phone mockup */
.anatomy {
  display: grid;
  gap: clamp(14px, 2vw, 22px);
}

.anatomy-cap {
  margin: 0;
  font-size: 10.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--olive);
}

.checks {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 20px;
}

.checks span {
  padding: 5px 11px;
  border: 1px solid var(--line-ink);
  border-radius: 999px;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.03em;
  color: var(--ink-muted);
  white-space: nowrap;
}

.label-shot {
  border: 1px solid rgba(19, 26, 21, 0.22);
  border-radius: 14px;
  overflow: hidden;
  background: var(--ink-3);
  box-shadow: 0 26px 50px -40px rgba(19, 26, 21, 0.6);
}

.label-shot img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.label-shot.is-missing {
  background:
    repeating-linear-gradient(90deg, transparent 0 79px, rgba(201, 242, 75, 0.07) 79px 80px),
    repeating-linear-gradient(0deg, transparent 0 79px, rgba(201, 242, 75, 0.07) 79px 80px),
    var(--ink-3);
}

.label-shot.is-missing img {
  visibility: hidden;
}

.anatomy-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0 clamp(18px, 2.6vw, 30px);
  margin: 0;
}

.anatomy-list > div {
  padding: 11px 0;
  border-top: 1px solid var(--line-ink);
}

.anatomy-list dt {
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.14em;
  color: var(--olive);
  text-transform: uppercase;
}

.anatomy-list dd {
  margin: 3px 0 0;
  color: var(--ink-muted);
  font-size: 13.5px;
  line-height: 1.55;
}

.anatomy-list dd b {
  display: inline-block;
  font-family: var(--mono);
  font-size: 19px;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--ink-text);
  margin-right: 9px;
  vertical-align: -2px;
}

.anatomy-list dd code {
  font-family: var(--mono);
  font-size: 12px;
  background: rgba(19, 26, 21, 0.06);
  padding: 1px 5px;
  border-radius: 4px;
  color: var(--ink-text);
}

/* install terminal */
.terminal {
  margin-top: clamp(26px, 3.4vw, 40px);
  border-radius: 18px;
  overflow: hidden;
  background: #0a100d;
  color: #edf1e6;
  box-shadow: 0 40px 80px -60px rgba(0, 0, 0, 0.9);
}

.terminal-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 13px 20px;
  border-bottom: 1px solid rgba(244, 242, 234, 0.1);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: #93a19a;
}

.terminal-head span b {
  color: #edf1e6;
  font-weight: 500;
  letter-spacing: 0.08em;
}

.copy {
  border: 1px solid rgba(244, 242, 234, 0.2);
  border-radius: 999px;
  padding: 6px 15px;
  background: transparent;
  color: #edf1e6;
  font: inherit;
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  cursor: pointer;
  transition: border-color 0.16s ease, color 0.16s ease;
}

.copy:hover {
  border-color: var(--lime);
  color: var(--lime);
}

.copy[data-copied="true"] {
  border-color: var(--lime);
  color: var(--lime);
  background: rgba(201, 242, 75, 0.1);
}

.terminal pre {
  margin: 0;
  padding: 20px;
  overflow-x: auto;
  font-family: var(--mono);
  font-size: 12.5px;
  line-height: 2;
  white-space: pre-wrap;
  word-break: break-word;
}

.terminal .c-dim {
  color: #6c7b74;
}

.terminal .c-cmd::before {
  content: "$ ";
  color: var(--lime);
}

.terminal .c-note {
  color: #93a19a;
}

.install-note {
  margin: 16px 0 0;
  color: var(--ink-muted);
  font-size: 13.5px;
}

.install-note a {
  color: var(--ink-text);
  text-decoration-color: var(--line-ink-strong);
}

/* ---------- why local ---------- */
.local .sec-head {
  margin-bottom: clamp(24px, 3.4vw, 38px);
}

.pills {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}

.pill {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 17px 22px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  font-size: 14.5px;
  color: var(--text);
  transition: border-color 0.18s ease, background 0.18s ease;
}

.pill:hover {
  border-color: rgba(201, 242, 75, 0.5);
  background: rgba(201, 242, 75, 0.04);
}

.pill::before {
  content: "";
  width: 7px;
  height: 7px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--lime);
  box-shadow: 0 0 14px rgba(201, 242, 75, 0.7);
}

/* ---------- faq ---------- */
.faq {
  border-top: 1px solid var(--line-strong);
}

.faq-item {
  border-bottom: 1px solid var(--line);
}

.faq-item summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 23px 0;
  cursor: pointer;
  list-style: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-q {
  font-size: clamp(17px, 1.5vw, 20px);
  font-weight: 560;
  letter-spacing: -0.015em;
  color: var(--text);
}

.faq-icon {
  position: relative;
  width: 30px;
  height: 30px;
  flex: 0 0 auto;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.faq-icon::before,
.faq-icon::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 11px;
  height: 1.5px;
  background: var(--text);
  transform: translate(-50%, -50%);
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.faq-icon::after {
  transform: translate(-50%, -50%) rotate(90deg);
}

.faq-item summary:hover .faq-icon {
  border-color: var(--lime);
}

.faq-item[open] .faq-icon {
  border-color: var(--lime);
  transform: rotate(180deg);
}

.faq-item[open] .faq-icon::after {
  opacity: 0;
  transform: translate(-50%, -50%) rotate(0deg);
}

.faq-a {
  padding: 0 clamp(40px, 8vw, 120px) 26px 0;
  color: var(--muted);
  font-size: 15.5px;
  line-height: 1.72;
}

.faq-a p {
  margin: 0;
  max-width: 74ch;
}

.faq-a a {
  color: var(--text);
  text-decoration-color: rgba(201, 242, 75, 0.5);
}

.faq-more {
  margin: 26px 0 0;
  color: var(--dim);
  font-size: 13.5px;
}

.faq-more a {
  color: var(--muted);
  text-decoration-color: var(--line-strong);
}

.faq-more a:hover {
  color: var(--lime);
}

/* ---------- footer ---------- */
.foot {
  margin-top: var(--sec-y);
  padding: clamp(40px, 5vw, 64px) 0 34px;
  border-top: 1px solid var(--line-strong);
}

.foot-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) repeat(3, minmax(0, 0.7fr));
  gap: 32px;
}

.foot-brand .brand {
  margin-bottom: 16px;
}

.foot-brand p {
  margin: 0;
  max-width: 34ch;
  color: var(--muted);
  font-size: 13.5px;
  line-height: 1.65;
}

.foot-brand .foot-note {
  margin-top: 14px;
  color: var(--dim);
  font-size: 12px;
}

.foot-col {
  display: flex;
  flex-direction: column;
  gap: 10px;
  align-items: flex-start;
}

.foot-h {
  margin: 0 0 4px;
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--dim);
}

.foot-col a {
  color: var(--muted);
  font-size: 14px;
  text-decoration: none;
  transition: color 0.16s ease;
}

.foot-col a:hover {
  color: var(--lime);
}

.foot-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px 28px;
  margin-top: clamp(34px, 4.4vw, 54px);
  padding-top: 22px;
  border-top: 1px solid var(--line);
  color: var(--dim);
  font-size: 12px;
  letter-spacing: 0.01em;
}

.foot-bottom .mono {
  font-size: 11.5px;
  letter-spacing: 0.02em;
}

/* ---------- responsive ---------- */
@media (max-width: 1120px) {
  .hero-grid {
    grid-template-columns: minmax(0, 1.62fr) minmax(250px, 1fr);
    gap: 40px;
  }

  .facts dd {
    font-size: 22px;
  }

  .pills {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 980px) {
  .nav {
    display: none;
  }

  .head-actions {
    margin-left: auto;
  }

  .hero-grid {
    grid-template-columns: minmax(0, 1fr);
    align-items: start;
    gap: 40px;
  }

  .hero-facts {
    max-width: 480px;
  }

  .sec-head {
    grid-template-columns: minmax(0, 1fr);
    align-items: start;
    gap: 18px;
  }

  .sec-lede {
    max-width: 62ch;
  }

  .out-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .anatomy {
    max-width: 680px;
  }

  .foot-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  body {
    font-size: 16px;
  }

  .brand-sub {
    display: none;
  }

  .clips {
    grid-template-columns: minmax(0, 1fr);
  }

  .step {
    grid-template-columns: 42px minmax(0, 1fr);
  }

  .step-tag {
    display: none;
  }

  .files li {
    grid-template-columns: minmax(0, 1fr);
    gap: 4px;
  }

  .compare-note {
    flex-direction: column;
    gap: 8px;
  }

  .track-src .rs::after {
    display: none;
  }

  .track-src {
    margin-bottom: 14px;
  }

  .track-reel > span {
    font-size: 12px;
  }

  .record-k {
    font-size: 9.5px;
    letter-spacing: 0.12em;
  }

  .faq-a {
    padding-right: 0;
  }

  .anatomy {
    max-width: 520px;
  }

  .anatomy-list {
    grid-template-columns: minmax(0, 1fr);
  }

  .foot-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 26px;
  }

  .pills {
    grid-template-columns: minmax(0, 1fr);
  }

  .pill {
    border-radius: 14px;
  }
}

@media (max-width: 480px) {
  h1 {
    font-size: clamp(2.4rem, 10.5vw, 3.1rem);
    letter-spacing: -0.035em;
  }

  .hero {
    padding-top: 34px;
  }

  .btn {
    padding: 14px 22px;
    font-size: 14.5px;
  }

  .head-btn {
    padding: 0 12px;
  }

  .facts dd {
    font-size: 20px;
  }

  .terminal pre {
    font-size: 11.5px;
  }

  .foot-bottom {
    font-size: 11.5px;
  }
}

/* ---------- zh typography ---------- */
body.lang-zh {
  font-size: 16px;
  line-height: 1.75;
}

body.lang-zh h1 {
  font-size: clamp(2.2rem, 4.15vw, 3.75rem);
  line-height: 1.2;
  letter-spacing: -0.02em;
  font-weight: 700;
  text-wrap: balance;
}

body.lang-zh .hero-grid {
  grid-template-columns: minmax(0, 1.85fr) minmax(260px, 0.9fr);
  gap: clamp(28px, 3.6vw, 58px);
}

body.lang-zh h2 {
  font-size: clamp(1.7rem, 2.7vw, 2.6rem);
  line-height: 1.22;
  letter-spacing: -0.02em;
}

body.lang-zh .lede {
  font-size: 16.5px;
  line-height: 1.85;
  max-width: 60ch;
}

body.lang-zh .sec-lede {
  font-size: 15.5px;
  line-height: 1.85;
}

body.lang-zh .eyebrow,
body.lang-zh .sec-index {
  letter-spacing: 0.12em;
}

body.lang-zh .facts dd {
  font-family: var(--mono);
}

body.lang-zh .faq-q {
  font-weight: 600;
  letter-spacing: 0;
}

body.lang-zh .step-body h3 {
  letter-spacing: 0;
  line-height: 1.35;
}

body.lang-zh .faq-a {
  line-height: 1.85;
}

body.lang-zh .clip-hits span,
body.lang-zh .facts dd .unit {
  letter-spacing: 0;
}

@media (max-width: 980px) {
  body.lang-zh .hero-grid {
    grid-template-columns: minmax(0, 1fr);
  }
}

@media (max-width: 480px) {
  body.lang-zh h1 {
    font-size: clamp(1.75rem, 7.6vw, 2.2rem);
    line-height: 1.32;
  }
}

/* ---------- motion preferences ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}